If the elevation of the Sun is  $30°$, then the length of the shadow cast by a tower at 150 ft height, is

$AB$ is height of tower is 150 ft

Angle of elevation of the Sun $=30°$

$BC=$ Shadow length

In $\Delta ABC$,

$\tan 30°=\frac{AB}{BC}$

$\frac{1}{\sqrt{3}}=\frac{150}{x}$

$x=150\sqrt{3}ft$